Improper input validation in IBM Power System E1050 \(9043-Mrx\) Firmware

CVE-2026-17503

IBM PowerVM Hypervisor FW1120.00 through FW1120.01, FW1110.00 through FW1110.31, FW1060.00 through FW1060.81, and FW950.00 through FW950.H3 is affected by a vulnerability in the partition firmware runtime boot configuration. An attacker with root access to a partition can maliciously alter partition nvram, causing the partition to fail to boot. This condition persists until operator intervention — deleting and recreating the partition configuration — to restore normal operation. Successful exploitation results in an integrity and availability impact.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.1 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H.

EPSS exploit prediction

EPSS: 0.001 (1.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 1st percentile — 1.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-17503: held from 0.001 to 0.001.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-17503?
CVE-2026-17503 is a medium-severity vulnerability in IBM Power System E1050 \(9043-Mrx\) Firmware, classified under Improper Input Validation. CVSS score: 5.1/10. Published 2026-09-24.
How severe is CVE-2026-17503?
Medium severity. CVSS v3 base score is 5.1 out of 10.